WASHINGTON — Republican Sen. Bob Corker is spending a lot of time lately talking to Democrats.

The freshman lawmaker from Tennessee unveiled his own 10-year, $4.5 trillion solution for averting the end-of-year, double economic hit of automatic tax hikes and spending cuts and then spoke briefly last week with Treasury Secretary Timothy Geithner. Deficit-cutting maven Erskine Bowles had forwarded Corker’s proposal to White House Chief of Staff Jack Lew.

Corker also was on the phone with Secretary of State Hillary Rodham Clinton for a 15-minute conversation about Libya and other issues. Not only is Corker a senior member of the Foreign Relations Committee, he is poised to become the panel’s top Republican next year, with a major say on President Barack Obama’s choice to succeed Clinton — possibly the divisive pick of U.N. Ambassador Susan Rice — and other diplomatic nominees.

Pragmatic and peripatetic, the conservative Corker has been deeply involved in negotiations on the auto bailout and financial regulations during his six years in the Senate, bringing the perspective of a multimillionaire businessman and a former mayor of Chattanooga to talks with Democrats and the White House.

“I don’t see him as a partisan,” said Democratic Sen. Mark Warner of Virginia, another multimillionaire businessman who has worked closely with Corker on banking and housing issues. “I think he’s somebody who’s willing to work with anybody who he thinks has a good idea.”

Next year, in the Senate’s new world order of a smaller Republican minority, the 60-year-old Corker is certain to play an outsized role, not only because of his high-profile standing on the Foreign Relations panel but because he is willing to work across the aisle in his eagerness to get something done. It is something of a rare trait in the bitterly divided Congress and one that often draws an angry response from the conservative base of the GOP.

It didn’t affect Corker politically. He scored a resounding win last month, cruising to re-election with 65 percent of the vote.

“I can count. I went to public schools in Tennessee and learned that to pass a bill it takes 60 votes and I know we have 45 going into next year,” he said in an interview with The Associated Press. “I came up here to solve problems, not to score political points, and yes, it was rewarding that after throwing ourselves into the most controversial issues there were and trying to solve things pragmatically we ended up in the place where we were in this last race.

“I’m more energized than I’ve ever been,” he continued. “The last two years of my first term were like watching paint dry because nothing was occurring and it was fairly discouraging and one has to ask oneself is this worth a grown man’s time.”

There were some doubts whether Corker, who made a fortune in real estate and had promised to only serve two terms, wanted to come back for more of a Congress riven by dysfunction and partisanship.

“At times I wondered if he would really run again,” said Tennessee Gov. Bill Haslam, who has known the senator for decades ever since Haslam’s older brother, Jimmy, the new owner of the Cleveland Browns football team, roomed with Corker at the University of Tennessee. “It kind of frustrates him, admirably so, when people aren’t focused on problem solving.”

Tom Ingram, a political consultant who has worked on Corker’s campaigns, said the senator deliberated on whether to run again. “He had to convince himself it was something worth doing before he did it,” Ingram said.

So Corker is back, with a black notebook that he grabs every morning to jot down problems and what he’d like to accomplish in a Senate where Democrats have strengthened their majority to 55-45, from 53-47.

On avoiding the so-called “fiscal cliff,” his 242-page bill challenges both Democrats and Republicans. Corker calls for a mix of tax increases and limits on Medicare and Social Security benefits. He would raise the Medicare eligibility age incrementally to 67 by 2027 and require wealthier retirees to pay higher premiums.

Although he would make all the Bush-era tax rates permanent, Corker wants to cap itemized tax deductions at $50,000, which would affect high-income taxpayers.

Corker recognizes that a final deal will be hammered out between Obama and House Speaker John Boehner, R-Ohio, but hopes his ideas earn some consideration.

A member of the Foreign Relations Committee since 2007, Corker has been frustrated with a committee that hasn’t produced an authorization bill in years and has become something of a backwater since its heyday of the 1960s and ‘70s. His goal is to make the panel more relevant, and he wants to conduct a top-to-bottom review of all foreign assistance and spending by the State Department and U.S. Agency for International Development.

High on the list for the panel early next year will be nominations, including Obama’s choice for secretary of state and possibly U.N. ambassador.

For all of Republican Sen. John McCain’s recent bluster about Rice and her initial, much-maligned account after the deadly Sept. 11 raid on the U.S. diplomatic mission in Libya, it is Corker who will render his judgment and provide a crucial vote on her prospects. Corker has described Rice as more of a political operative but has avoided saying definitively where he stands on the potential nominee.

While other Republicans criticized Rice after her comments based on talking points prepared by intelligence officials, Corker traveled to Libya the first week of October to meet with officials there and learn more about what happened. The senator has traveled to 48 countries since he joined the committee.

“He’s viewed as conservative, but he’s independent,” said former Republican Gov. Don Sundquist.

After being appointed state finance commissioner by Sundquist, it was Corker who brought together various factions and helped Tennessee lure the Houston Oilers to the state. To complete the deal, Sundquist had to work with Nashville Mayor Phil Bredesen, a Democrat he had just defeated in the gubernatorial race.

Corker was like a child trying to make peace between warring parents. It paid off with the arrival of the Tennessee Titans in 1997.

One of Corker’s first jobs was good training for moving immovable objects, whether home-state politicians or members of the Senate. In college, Jimmy Haslam and Corker had a small business doing odd jobs, including removing tree stumps.

“I always give them both a hard time that the biggest thing they removed was the axle from two or three trucks that they ripped out trying to get the stumps out,” said Gov. Bill Haslam. “They were better at axle removal.”